AirHint found the following cheapest return flights from Ontario (ONT) to Keflavik (KEF) in August 2025 (see full year).
Return flights
| 20 Aug - 13 Sep | Frontier Airlines | ||
| 25 Aug - 29 Aug | Frontier Airlines | ||
| 25 Aug - 28 Aug | British Airways |
Also check the deals for one-way flights from Ontario to Keflavik in August.
The deals are updated regularly. The prices may go up as tickets are purchased by other travellers. Only the cheapest flights are offered. Select a price to book and secure these cheap prices.
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